Pinking under load on stock 318ci

[Glen63]

Well finally had the Charger out and about a few times and now can get to know the motor a bit.

I am getting pinking under acceleration, had the timing checked and it was set at recommended, still pinking a bit so, retarded it a little more.

Mixture setup roughly correct and running on a new stock carb, new air filter, new NGK plugs, new leads, new dissy cap, rotor arm.

The automatic advance and retard on dizzy is working OK.

So did a compression test on all cylinders, this is an original, rebuilt stock engine, so was not expecting much. 7 cylinders all read around 168-172, but cylinder number 1 is only reading 132.

So is it possible I have a stuck hydraulic lifter ? Do I even have hydraulic lifters on this engine ?

Did make the mistake of putting BP high octane petrol in, but now back to standard unleaded.

Any of you engine guys got any ideas what I should be looking for or any other thing I could try, I don't want to do any damage by driving to much, but the summer is here and I want to be out

[Pete]

If stock you will have hydraulic Lifters, if it were stuck I thought you would have a mis-fire or backfire / backfire through Carb...it may be worth lifting the rocker box for a look-see.....

I assume the heads have been off and de-coked?

Is the Damper marking actually at TDC? the dampers can shift on the rubber element....

[Glen63]

Thanks for reply Pete

No heads have not been off at all, did not want to start stripping engine down in the middle of summer, wanted to drive it.

Will check the damper marking is at TDC, how ?

[autofetish]

Take out plug on Cylender 1

take off valve covers

turn engine by hand till piston is at TDC ( screw driver in hole BE CAREFULL)

[MilesnMiles]

The higher octane fuel should help with pinking.

[Dave999]

turn over until no.1 piston is at the top of the fireing stroke not exhaust stroke

however the piston dwells at the top for a good few degrees

so do this instead

smash up an old spark plug and wind a flat ended bolt though its guts so it stick out about 1 inch

turn engine Back 1/4 of a turn so the piston is down

put in modified plug

check distributor rotor is on the way towards no.1 cylinder lead as you
wind engine over by hand slowly forwards until the piston hits your spark plug/bolt - stopper.

check that TDC is a little way in the future (if its not you are on exhaust stroke and your dizzy will be approaching no.1s partner in the firing order - if so fix the issue by taking out stopper keep going forward until piston is on way down again and put stopper back in


when you wind forward to the stopper
draw a line on the balancer from the 0 in the timing cover tang

then wind the engine backwards until it stops again draw a line on the balancer from the 0 on the timing cover tang

use a strip of paper to measure between the marks

cut it to the exact length of the space between the marks (ruler and Stanley knife)

fold it exactly in half

the line at the fold halfway is used to identify TDC. When the paper is lined up with your two new lines on the balancer its middle fold should match with 0 degree mark

if it doesn't

draw a nice thin line on the balancer in white or yellow paint pen where the fold is

this is TDC.


Dave

[mad machs]

Or, just keep backing the timing off until it doesn't pink, if it runs ok afterwards, leave it be.

Re the low reading on No1....Chuck a bit of oil down No1 plug hole, crank it over by hand then re-do the CR check, if it gives a better reading, a piston ring issue may be evident.

[MilesnMiles]

As Mike said, but be aware that you don't have to move the dizzy much at all to get the result you need. Recent trial runs with my car showed that nudging the dizzy back just a millimetre or so would lessen detonation.

[Glen63]

Wow Dave99 thats is a comprehensive answer, sounds like a lot of knuckle skin lost with all that winding the engine back and forth by hand, but suppose it would be good to know TDC once and for all.

Will be lazy first and mark where dizzy is at moment and try a little more retard, if that no joy, then onto smashing up spark plug

Will try a little oil in Cylinder 1 as well, to see if it helps compression.

Thanks for all the suggestions lads.

[Glen63]

Took the Charger out for a trip the other day and stopped 4 times to adjust the timing, got to a point, where I had made the pinking real bad.

So went back to the markings where I had started and tried again, found the sweet spot and it pulled real well and felt so much better. Now feels great and I had to watch my speed, as I was so tempted to.

Will now clean off all old marks and mark the distributor where it is now.

Happy days

[Pete]

Well done!

Have a good hoon now!

[Glen63]

Now got to get the front wheels pointing in right direction !!!

Have not had alignment, camber etc done, since rebuilding front suspension, need to book it in the place at Milton Keynes that knows Chargers etc

What was there name ? I thought I had bookmarked it, but cannot find it now.

[Glen63]

Think I was thinking of Monkfish Performance, other side of Milton Keynes to me over here in Suffolk.

Sure there was a tread about how good they were at alignment etc.

[morgan]

Monkfish performance. ('roger' on here).
Awesome. Make sure your bolts and bushes are in good order for best results. The man is a wizard.

[Steve]

Sorry if I have misread this Glenn but, in my limited experience, our cars generally need the timing to be advanced more than stock rather than retarded. Stock timing wont work with modern fuels. I always try it at 10 deg btdc then take it from there. A lot of owners land on around 16 to 18 deg btdc and have to use a limiter plate from Jon at FBO to 'cap' the total timing to 34 deg or so.

Ive never found that retarding the timing from stock helped anything...it always makes things worse.

Cheers Steve